#define _CRT_SECURE_NO_WARNINGS 1

#define PI 3.14
#include<iostream>
using namespace std;

class circle
{
public:
	int r;

	double calcRound()
	{
		return 2 * PI * r;
	}
};

int main()
{
	circle C1;
	C1.r = 2;
	cout << "Round=" << C1.calcRound() << endl;
	return 0;
}